Bicycle quick-release mechanisms are utilized to allow a bicycle wheel to be quickly disconnected from the bicycle frame for repair, maintenance, securement to a bike rack, or shipping when the bicycle is not in use. Bicycle wheel quick-release (“QR”) mechanisms are available for both the front and rear wheels. Conventional quick-release mechanisms utilize a quick-release lever assembly located on one side of one of the bicycle dropouts—front and/or back. The term “dropout” herein refers to the wheel mount at the fork or rear of the bicycle, whether an open slot or a capturing hole for the axle to be secured within.
The quick-release lever assembly attaches to one end of a skewer shaft. The other end of the skewer shaft is attached to a manually operated nut. In use, to remove a bicycle front wheel, the quick-release lever is operated to an open position. In the open position, the skewer assembly is not clamped to the front forks of the bicycle. To completely remove the bicycle front wheel, in some common designs, the nut on the end of the skewer opposite the QR lever must be loosened at least several turns. The bicycle wheel can then be removed by removing the wheel from downwardly oriented dropout slots in the forks. Note that the design is called a “quick-release”, but the secondary retention devices require that the nut be unscrewed extensively such that it really is not quick.
This design also has the disadvantage of the wheel hub axle not being captured in through-holes in the forks. Due to this disadvantage, the front wheel of a bicycle with this type of quick-release design has the potential to fall-off the dropout slots in the forks if an inadequate clamping force of the skewer assembly to the front forks is applied by operation of the quick-release lever of the quick-release assembly. This is of particular concern where disc brakes, in lieu of rim brakes, are utilized. On rim brakes, the moment arm from the axle is much greater and is about the same as the radius of the wheel, so the applied braking force at the rim is relatively small. However, on disc brakes, which are located proximal the hub axle, the moment arm about the axle is much smaller than the radius of the wheel, so the applied forces on the wheel brake disc by the brake pads are much larger. In addition, these applied forces by the brake pads may be oriented in a generally downward direction, if the brake pads are mounted aft of the lower portion of the forks.
Due to this configuration, there is a potential for bicycle front wheels with disc brakes and downwardly oriented dropout slots to have the front wheel come off during use of the bicycle, particularly when the tool-less quick-release assembly has not been properly adjusted to provide an adequate clamping force. Breakage of the dropout tabs and/or the jacking out of the axle from the vehicle frame member may also result during use, potentially causing injury to the rider. Due to this risk, instead of using conventional open dropout slots, some bicycle structures have through-holes instead of dropout slots. However, this dropout design requires the skewer rod to be removed from the fork through the through-holes in order to remove the wheel. To facilitate this, a manually operated nut may be attached to the skewer rod, which may be threaded into the quick-release assembly. The manually operated nut in this type of fork design must be unscrewed completely to allow the skewer rod to be disengaged from the component it is threaded into. Once this occurs, the skewer rod is removed, which allows the bicycle front wheel to be removed from the front forks (and parts to be lost). To reinstall the front wheel, the bicycle wheel is placed between the front forks and the manually operated nut with the attached skewer rod is threaded into the appropriate component. However, the unscrewing (or loosening) and tightening of the manually operated nut while also properly locating the wheel between the forks may be difficult to accomplish consistently and adequately. In addition, the thread engagement of the skewer rod to the component the skewer rod threads into must be of a proper length in order to provide a proper clamping force of the QR skewer assembly to the forks when the quick-release lever is closed. Adequate and consistent tension with the nut and skewer is not always obtained, especially by an inexperienced user.
Accordingly, a need exists in the art for a bicycle wheel quick-release skewer assembly that utilizes vehicle dropouts or rear mounts with through-holes instead of dropout slots that easily allows a bicycle wheel to be removed from the dropouts and reinstalled to the without having to loosen (and completely remove in some instances) and tighten a manually operated nut attached to the tensioning member. A need also exists in the art for a bicycle quick-release mechanism that utilizes through-holes instead of dropout slots that allows for reinstallation of the bicycle front or rear wheel that does not require precise hand tightening of the manually operated nut in order to achieve a proper clamping force of the bicycle quick-release skewer assembly.
Disc brake mounts are secured near the dropouts to secure the disc brake mechanism. At times, the user may wish to change the size of the brake disc, requiring the user to secure an adaptor to the mount to align the brake pad mechanism with the different brake disc. For example, the user may move from a 140 mm disc to a 160 mm disc in order to have increased leverage for additional stopping power. Alignment of the brake pad mechanism is vital to a smooth, free-running wheel and to effective braking. However, this can be difficult with a conversion to a different size disc. Removing the heat from the disc brake mechanism can also prove to be difficult.